Japan's Ulvac has become the first company to put solid-state thin-film lithium batteries into mass production, it claimed this week.
Ulvac's pitching the power source as an alternative to today's lithium-ion rechargeables, specifically by stressing that its design contains no liquid electrolyte and therefore is incapable of... …

As long as...

Does not prevent it from burning

Lithium + water ... Boom... Lithium + Oxygen... Boom... So as far as these batteries not exploding... As one of my favourite characters said in Babylon 5:"No boom today... Boom tomorrow... There will always be a boom tomorrow".

In other news...

:This leaves just one question begging

All of the above

Capacities are ~ 0.3mA/cm2 or more but they are so thin you can pack a lot of cm2 into a 1mm thick package! Discharge rates of 25C at room temp and 100C at 80oC and 300C at 150oC! The batteries can be OPERATED at 150oC so BOOM is not only NOT true,higher temps enable improved operation. Bare Li films from these batteries in the lab are completely safe even when heated to 150oC. Throw one (or even a piece of Li foil) into water and you get heat and H2 released, but there is nothing to burn. The only reason Li ion batteries burst into flames is the presence of the highly volatile solvents in the liquid electrolyte that reach flash point when the batteries overheat. There's a company in Atlanta that makes these thin film all solid state cells/batteries and you can get samples to try for yourself.